Allan Kustok is accused of killing his wife Anita "Jeanie" Kustok in their Orland Park home as she slept. On Tuesday, a crime scene reconstruction expert spent the entire day on the witness stand.

For the first time since the Allan Kustok trial began, Cook County State's Attorney Anita Alvarez sat in as prosecutors came close to wrapping their case with their star witness, blood spatter and reconstruction expert Rod Englert.

Paid close to $100,000 for his expertise during the past three-and-a-half years, Englert gave jurors a crash course on blood stain patterns. Pencil dot blood stains were found on Allan Kustok's shorts, t-shirt and glasses, clothing that prosecutors say he wore when he allegedly shot his wife, Jeanie to death. Englert testified that the microscopic blood spatter is consistent with the state's allegation that Kustok fired a powerful .357 caliber revolver into wife's left cheek.

Kustok claims Jeanie died from a self-inflicted gunshot wound on the morning of September 29, 2010. He told police he found his 58-year-old wife dead on her back with her hands across chest, the gun held in her right hand, a position Englert concluded through a scene reconstruction that would not be possible with a suicide or accidental shooting.

Englert told the jury Jeanie Kustok's wound is on an angle, which he says means the gun was elevated when it was shot. In addition, Englert says, blood spatter found on both sides of the gun is also consistent with a gun pointed from an angle, not from the victim firing it at herself.

With no soot or burn marks found on Jeanie Kustok, Englert concluded the person who shot Jeanie Kustok was the person wearing the shorts, t-shirt and glasses.

Englert will return to the witness stand Wednesday morning to be cross-examined. After that, the state will rest. The defense has its own witnesses, which also includes an expert.